Power reverse gear



Nov. 3, 1931. M. H. ROBERTS POWER REVERSE GEAR Qriginal Filed Feb. 2 6, 192] ATTORNEYS nK N@ M E 1 E v f m Am. m r, op S PfenteaNv'. s, 193,1,k y' l MONTAG-UE n. EoBEEfrsorv ENGLEWOOD, NEW JEE sEY,"nssIGNoE y'ro'FRANKLIN .EAIL- WAY SUPPLY colvrrANYmE NEW YoEx, N. Y., i,A yransomvoEAfrroN-,or DELAWARE roWEE EEvEEsEoEAfEy* j Y Origin-a1 application jiled February 26,192.1, Seria February 5,v 1924.

This inventionrelates to power reverse gears such, as arefused, for example, on locomotives, and itis a divisionof my copend-l ing application Serialy No. 448,044,1.iled February 26th, 1921, and since issuedy as Patent No; 1,500,685, OnJuly 8, 1924.

' Briefly, the invention has to ,dov with a power reverse gear of the servo-motor type, havingadirectconnection between the valve andthe piston byvirtue ofvwhich combination levers vand other mechanism involving lost motion may be dispensed with, and a gear obtained which is precise in its operation, with the piston and, therefore, the valve motion automaticallyl maintained in any desired position/of a Acut off. The operfy ating connection. between the' valve and the piston' is such that the vconnectionrmay be readily adjusted manually when it is'desired to shift the piston to adjust vcut oif but, during automatic operation", the valve and piston'move together. The operating connection comprises a screw kthreaded shaft, in the' preferred embodiment of my invention.

My invention contemplates a simple, compact and effective arrangement and'association or organizationof parts in a gear of this type. The foregoing together :with suchv other objects as may hereinafter appear, orv are incident to my invention, I accomplish by means of a construction, the preferredembodiments of which are illustrated inthe accompanying ldrawings, kwherein .Figgl is a longitudinal section through one form of reverse gear embodying my improvements; andFig. 2 is a similarsection through another form oftheinvention. Referring now tofFig. 1,' the yreferencenum'eral 7 vdesignates 'the power reversegear cylinderwhich is attachedfrto the locomotive boiler at a vpoint intermediatev the cab and the valve m-otion.A This cylinder'has two heads S-and- 9 and thefpiston-10, the piston rod-11 of which is made hollow. 'y The piston rod'extends throughthe head 9 and'ijs suit. ably'packed and is provided at'its*` free end with .the eye 12 for connection with the reach rod V(n'ot'shown)y leading to the link motion. The pistonvis made in two halves suitably secured together, one half having the hollow and exhausted from the other.

piston 11 preferably formed integrally therewith, and the'other half having 'a hub 1,3. The hubj13 Yis providedi'with a centralfaperture ,which is threaded andthe hub is also externallythreaded to receivelfthe ytubular member The piston is provided with ,af'pairj60 of '.spacedi packing rings-r-preferably cup leathers-as shown, and between the packing there'is ya groove 15 `extending annularly of thejpiston, such. groove being connected to the interior of the piston and thence to the atmosphere bymeans of a port'15a. Leak` agethus occurs'to the atmosphere instead of the low pressure side of the piston.

The headgis so shaped and constructed that it cooperates with the A,cap 16l to actas favalve chest in which the slide valve 17 is `mounted.` The 'arrangement of the ports and the piping'will notibe described for the reafsonfthatno specific claims thereto are made herein,-and itwill suiice for the purposes of this specification to point out that when the valve moves from the neutral position shown, ,.'olxriegwayr or the other, pressure is introduced into the cylinder. lon one facel of the piston I The operating connection between the valve and the piston comprises the screw. threaded 'shaft 18y and the tongue19 which is carried fron thekshaftand engagesthe slide valve 17. The, forwardend ofthe shaft 18 is threaded 'into the hub lfand` is free to work within the tubular member 14 which is packedl with greas'eor filled lwith some "other lubricant.y

The'rear end of the shaft 18 is squared to -Vit the squared recess in the sleeve 20, such 'sleeve extending out 'throughthe head and beingy suitably packed. Extending rearward'-y `ly from the ksleeve 20 to the cab is the rotary ,hand operating means21,"a portion only of which is shown. f

:pistonto adjustput-oif, the hand operating means 21 isrotated which in turn rotates the shaft18, causing it to lengthen or shorten lwithrespect.tothe piston, as the casemay be, correspondingly"moving' the valve and i yThe operation isi as follows: To shift the I allow an `exhaust openingthe-'appropriate ports `to admit presvsure to and exhaust pressure, from opposite faces of thepiston.- As long' as the shaft 'is `being rotated, the valve Will be held in open position,V and yassoonas rotation of the shaft'c'eases, movement of the piston" will f cause the 'valve t0 moveto Closed'position,

bringing ,the lpiston to rest. In case the ypisaperture, a valveand a shaft having a direc connection with the valve and threads engag ing said piston aperture.

In testimony .vvhereol,` I have 'hereunt signed-my name.; f

.. MoNrAGUEz H. ROBERTS.

by'virtu'e'f 'a drop Ain pressureon one face or the other, the valve Will immediately Inove-VIA with it,` opening the appropriateports tol pressure tobring the-piston; v

back tothe pre-selected position,`V 4 Y The advantages of the arrangement are 'l `that praetically no yvorkinglvparts are eX"- "posed,',th`e valve chest is 1in line with thefeyl- 'aider andthe shaft in' l'iewith the piston 25 tion is adapted to a'piston formed integrally rod7,"inaking the device Compact and simple g in Const'r'uetio11-V The vp'ulljon all Vparts is direct, the screw is easilyV lubricated, and-v is 'excluded from the lubricant.

The constructionl of Fig. 2 is, in allne'ssentialsi, `thes'ame as that already described.

Inthis arrangement ythe operating connecf the piston rod, the parts beingin a single piece instead vo'f'being split. The piston v l engaging saidfpistonapertre.

Iclairru Y y. 4 1, In a locomotive servo-motor power reversegear, a cylinder, apistoii havinga oen` i tral hollow rod, a valve, and 'anvoperating rod y'constituting a directoperating connection -betvveenthe valve and the piston and extending into the hollow piston rod.

2. Ini/a locomotive; servo-motor povverref f verse gear', a piston having a central threaded aperture, a valve anda shaft having a di-A reet connection With kthe'valve and threads Y i 5.3.1In a locomotive vservomotor povver "reverse gear, a threaded piston, a valveand a l piston having a Central hllovv rod intorwhioh shafthavin'g a direetfconnection With'nthev valveand thread'sengag'ing the'piston ,-fsaid anend of the shaft iszadap'ted to extend.

f4. In a loe'omotive'- servo-niotorpvverra verse gear, a threaded piston, a valve and aV .piston having ahollovv rod-into Which lan endol:l the shaft is adapted to-eXtend, together'With a tubular Vhousing Withinthe rod threaded intothe piston.'

yshafthavinga. direct connection With the valve and Lthreads engaging: the piston, said adapted lto receive, the end of the "shaft i l I 5'. Ina locomotive servom'otor poiverireverse gear@v piston "head having a threaded f I 

